GB2256633A

GB2256633A - Carton for packaging liquids

Info

Publication number: GB2256633A
Application number: GB9114752A
Authority: GB
Inventors: John Richard Solon Duschnitz
Original assignee: Individual
Current assignee: Individual
Priority date: 1991-06-10
Filing date: 1991-07-09
Publication date: 1992-12-16
Also published as: GB9112392D0; GB9114752D0

Abstract

A carton has a sealed linear edge 12 at its upper end of which the ends are folded over to form triangular flaps 18 overlying the sides of the carton. A pouring orifice 20 is formed on the underside of at least one of the flaps 18, the orifice being sealed by adhesion of the flap 18 to the side of the container. <IMAGE>

Description

CARTON FOR PACKAGING LIQUIDS Field of the invention The present invention relates to a carton for packaging of liquids.

Description of the prior art Conventionally, liquid foodstuffs, such as milk and orange, have been sold and stored in bottles. Because of cost considerations, more recently disposable packaging has been used, a very common being a rectangular cardboard carton lined with a layer of safe plastics material such as polythene.

The difficulty that this form of packaging causes to the user is that they are difficult and awkward to open and to use. Commonly, the cartons have a folded over triangular flap at the top and markings are placed on this flap for the user to cut along it with scissors. In some cases, the flaps are designed to be torn to create a spout. It is difficult to grip the carton while the flap is being cut or torn and because the sides of the carton are being squeezed in the process, the liquid frequently spills out.

This problem is well recognised and various solutions have been implemented to simplify the task of opening the carton.

For example, it is known to form a hole in the top of the carton and to seal the hole by an adhesive tab which may be peeled off to allow the liquid to be poured out. In this case, because of the position of the hole, it is difficult to pour the liquid out without spillage and there is still the problem that the squeezing of the carton, to grip it while the adhesive tab is being peeled off, can cause the liquid to spurt out.

Obiect of the invention The invention seeks to provide a carton which may easily be opened and from which the liquid contents can easily be poured out without risk of spillage.

Summarv of the invention According to the present invention, there is provided a carton having a sealed linear edge at its upper end of which the ends are folded over to form triangular flaps overlying the sides of the carton, characterised in that a pouring orifice is formed on the underside of at least one of the flaps, the orifice being sealed when the flap is adhered to the side of the container and being opened automatically when the flap is separated from the side of the container.

By virtue of the fact that in the invention the seal on the pouring orifice is automatically broken when the flap is raised from the side of the container, the carton can be used without cutting or tearing any part of the flap, nor indeed by peeling any tabs or stickers from the carton.

The risk of accidental spillage during opening of the carton is virtually eliminated by the invention. While there is a fold in the flap, liquid cannot easily reach the pouring orifice even if the carton is slightly squeezed because of the obstruction presented by the fold line. By the time the flap is raised sufficiently to open out this fold and permit the the liquid to be poured out smoothly, the orifice is above the liquid level and the liquid can only be poured out by tilting the carton.

For smooth pouring, it is possible to make do with a single orifice in the carton if the carton is gently squeezed while pouring. If two orifices are provided on opposite sides of the carton, then one will act as a vent for the other.

It is conventional for a carton to be formed of a cardboard coated on its inner surface with at least one impervious layer, for example of plastics material or metal foil. It is possible, to form the pouring orifice so that the cardboard is removed from the orifice but for the liquid impervious layer to remain intact across the orifice. If the flap is stuck to the side of the carton by an adhesive which is stronger than the tearing strength of the impervious layer, then the seal across the pouring orifice will be torn as the flap is raised. This construction has the advantage that the liquid never comes into contact with the adhesive and the gluing of the flap to the side of the carton can easily be performed during filling of the cartons in an automated process.

In alternative embodiment of the invention, a separately formed tab is adhered on one side prior to filling of the cartons over the pouring orifice and the other side of the tab is adhered using a stronger adhesive to the side of the carton. Because the adhesives are of different strengths, the tab will remain on the side of the carton and will separate from the pouring orifice when the flap is raised.

The invention will now be described further, by way of example, with reference to the accompanying drawings, in which: Figure 1 shows a perspective view of a closed carton, Figure 2 is a similar view showing a open prior art carton with the triangular end flaps bent up, Figure 3 is a view similar to that of Figure 2 showing a carton of a first embodiment of the invention, Figure 4 shows an alternative embodiment of the invention at one stage during the filling process, and Figure 5 is a view similar to that of Figure 3 showing a carton in accordance with a further embodiment of the invention.

Figure 1 shows a common type of liquid carton being a rectangular tube of which the upper end is sealed along a rectilinear edge 12 and triangular flaps 18 at each end of the sealing edge 12 are folded over to overlie the sides of the carton. Prior art cartons of this type are well known and a carton of the invention has the same outward appearance when closed and sealed.

To open a prior art carton of the this type, one raises one or both of the triangular end flaps 18 as shown in Figure 2 and one cuts or tears along a line 14 which is either drawn or perforated. The carton is unavoidably squeezed during this tearing action and very often some liquid spillage occurs.

In the invention, the underside of the flap 18, as shown in Figure 3, has a pouring orifice 20 which is of any suitable shape, for example round or triangular. Prior to unbending of the end flap 18, this orifice is sealed by virtue of the flap 18 being secured by glue 22 to the side of the container. The carton material has an impervious lining of plastics material or metal foil and it is this layer that is glued to the side of the carton. When the triangular end flap 18 is prized up, the lining is torn and remains stuck to the glue 22. To prevent the carton from being opened accidentally further spots of glue may be placed on the end flap 18, such as the spot 24 illustrated in the drawing.

To open this carton, one may place the carton with its base on a flat surface and raise the triangular flap 18. As the flap 18 is being raised, the fold line connecting the flap 18 to the side of the carton 10 acts as an obstruction to liquid flow so that little liquid can escape even if the carton is pressurised by being squeezed. The obstruction will only be removed when the flap 18 is fully raised as shown in Figure 3, but by that time the orifice 20 is above the liquid level and no liquid will be spilled from it.

To pour out liquid from the carton 10, it is tilted until the liquid escapes from the orifice 20. In the absence of a vent hole, fluid flow can be maintained by squeezing the carton but a vent hole, if preferred, can be provided by having orifices 20 in both triangular end flaps 18.

It is possible for glue used in the spot or spots 24 to be of the type that remains tacky after initial separation, thereby allowing the carton to be resealed.

The filling of the carton in Figure 3 requires only that the cardboard be removed or weakened from within the orifice 20 leaving only the impervious layer intact. After the carton is filled in the usual way, the edge 12 is sealed and its end folded over. The only additional step required for implementation of the invention is the dabbing of glue over the area of the orifice 20 prior to the end flaps being folded down.

Figure 4 shows an alternative embodiment which is essentially the same as that in Figure 3 but uses a separate adhesive tab 26 to seal off the pouring orifice 20 before the carton is filled. Thus in Figure 4, the tab is shown sealing off the orifice 20, the latter being shown only in dotted lines. Glue is used to adhere the tab 26 to the sides of the container 10 as the end flap is folded down and care is taken to select a glue which adheres more strongly to the tab 26 that the bond between the tab 26 and the end flap 18.

Therefore, when the end flap is raised from the position shown in Figure 1, the tab will end up being transferred from the end flap 18 to the side of the container leaving the carton, when open, looking the same as the carton in Figure 3.

To assist in the transfer of the tab 26 from the triangular end flap 18 to the side of the container it is advantageous to leave an unglued edge on the part of the tab 26 nearest the apex of the triangular flap 18 on the side of the tab 26 facing the aperture 20. The other side, however, is adhered over its entire extent to the side of the container. The effect of leaving an unglued edge will be that the tab will be gradually peeled off the hole as the triangular end flap is raised, ensuring a reliable uncovering of the aperture 20.

The embodiment shown in Figure 5 is a modification of that shown in Figure 3, the essential difference being that the semicircular aperture 32 is formed on the crease between the triangular end flap 18 and the side of the container. The container is once again lined with an impervious material and the cardboard alone (not the lining material) is weakened or cut through along a semi-circular line which terminates on the crease. Prior to folding over of the end flap 18, glue is placed on to the region bounded by this line so that it adheres to the side of the container. As the end flap 18 is raised, this region 30 remains stuck to the side of the container, thereby opening a semi-circular aperture 32 through which the contents of the container can be poured out. The line need not of course be semi-circular and may be of any other configuration suitable for pouring and for ease of opening.

Claims

1. A carton having a sealed linear edge at its upper end of which the ends are folded over to form triangular flaps overlying the sides of the carton, characterised in that a pouring orifice is formed on the underside of at least one of the flaps, the orifice being sealed when the flap is adhered to the side of the container and being opened automatically when the flap is separated from the side of the container.

2. A carton as claimed in claim 1, having two orifices formed one in each triangular flap, whereby one orifice may act as a vent while the liquid content of the carton is poured out of the other.

3. A carton as claimed in claim 1 or claim 2, wherein the carton is formed of a cardboard coated on its inner surface with at least one impervious layer and wherein the pouring orifice is formed by removing, cutting out or weakening the cardboard from within the orifice while leaving the impervious layer intact and adhered to the side of the container.

4. A carton as claimed in claim 3, wherein the aperture is formed adjacent the crease between the triangular flap and the side of the container.

5. A carton as claimed in claim 1 or claim 2, wherein a separately formed tab is adhered on one side prior to filling of the cartons over the pouring orifice and the other side of the tab is adhered using a stronger adhesive to the side of the carton.

6. A carton as claimed in claim 5, wherein the edge of the tab nearest the apex of the triangular flap is not glued on its side facing the triangular flap, whereby the tab may be peeled gradually from the flap when the flap is separated from the side of the container.

7. A carton for packaging a liquid constructed and adapted to operate substantially as herein described with reference to and as illustrated in Figure 3, Figure 4 or Figure 5 of the accompanying drawings.